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  <title>Sets write file buffering on the given stream</title>
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    <li>Sets write file buffering on the given stream</li>
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  <div id="layout-content"><div id="function.stream-set-write-buffer" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">stream_set_write_buffer</h1>
  <p class="verinfo">(PHP 4 &gt;= 4.3.0, PHP 5, PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">stream_set_write_buffer</span> &mdash; <span class="dc-title">Sets write file buffering on the given stream</span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.stream-set-write-buffer-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>stream_set_write_buffer</strong></span>(<span class="methodparam"><span class="type">resource</span> <code class="parameter">$stream</code></span>, <span class="methodparam"><span class="type">int</span> <code class="parameter">$size</code></span>): <span class="type">int</span></div>

  <p class="para rdfs-comment">
   Sets the buffering for write operations on the given <code class="parameter">stream</code>
   to <code class="parameter">size</code> bytes.
  </p>
 </div>


 <div class="refsect1 parameters" id="refsect1-function.stream-set-write-buffer-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>
    
     <dt>
<code class="parameter">stream</code></dt>

     <dd>

      <p class="para">
       The file pointer.
      </p>
     </dd>

    
    
     <dt>
<code class="parameter">size</code></dt>

     <dd>

      <p class="para">
       The number of bytes to buffer. If <code class="parameter">size</code>
       is 0 then write operations are unbuffered.  This ensures that all writes
       with <span class="function"><a href="function.fwrite.html" class="function">fwrite()</a></span> are completed before other processes are
       allowed to write to that output stream.
      </p>
     </dd>

    
   </dl>

  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-function.stream-set-write-buffer-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   Returns 0 on success, or another value if the request cannot be honored.
  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-function.stream-set-write-buffer-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-3781">
    <p><strong>示例 #1 <span class="function"><strong>stream_set_write_buffer()</strong></span> example</strong></p>
    <div class="example-contents"><p>
     The following example demonstrates how to use
     <span class="function"><strong>stream_set_write_buffer()</strong></span> to create an unbuffered stream.
    </p></div>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$fp&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">fopen</span><span style="color: #007700">(</span><span style="color: #0000BB">$file</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"w"</span><span style="color: #007700">);<br />if&nbsp;(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;if&nbsp;(</span><span style="color: #0000BB">stream_set_write_buffer</span><span style="color: #007700">(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">0</span><span style="color: #007700">)&nbsp;!==&nbsp;</span><span style="color: #0000BB">0</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;changing&nbsp;the&nbsp;buffering&nbsp;failed<br />&nbsp;&nbsp;</span><span style="color: #007700">}<br />&nbsp;&nbsp;</span><span style="color: #0000BB">fwrite</span><span style="color: #007700">(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$output</span><span style="color: #007700">);<br />&nbsp;&nbsp;</span><span style="color: #0000BB">fclose</span><span style="color: #007700">(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">);<br />}<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

   </div>
  </p>
 </div>


 <div class="refsect1 seealso" id="refsect1-function.stream-set-write-buffer-seealso">
  <h3 class="title">参见</h3>
  <ul class="simplelist">
   <li class="member"><span class="function"><a href="function.fopen.html" class="function" rel="rdfs-seeAlso">fopen()</a> - 打开文件或者 URL</span></li>
   <li class="member"><span class="function"><a href="function.fwrite.html" class="function" rel="rdfs-seeAlso">fwrite()</a> - 写入文件（可安全用于二进制文件）</span></li>
  </ul>
 </div>


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